Continuous imaging apparatus

ABSTRACT

There is disclosed an electrostatic imaging apparatus which incorporates the continuous use of a reusable, flexible imaging member in an imaging system in conjunction with full-frame exposure.

United States Patent Clark CONTINUOUS IMAGING APPARATUS [72] Inventor:Harold E. Clark, Penfielcl, NY.

[73] Assignee: Xerox Corporation, Rochester, NY.

[22] Filed: April 30, 1969 [21] Appl. No.: 820,573

[52] US. Cl ..355/3, 355/16 [51] Int. Cl. ..G03g 15/00 [58] Field ofSearch ..355/3, 16

[56] References Cited UNITED STATES PATENTS 3,244,083 4/1966 Gundlach m....3/3

[451 Oct. 10, 1972 2,979,026 4/l 96l Reuter .Q ..355/5 X 3,299,787l/l967 Kolb ..355/l6 X 3,432,231 3/1969 Gardner .Q. ..355/l6 X PrimaryExaminer.lohn M. Horan Attorney-James J. Ralabate, Donald C. Kolasch andAlbert A. Mahassel [571 ABSTRACT There is disclosed an electrostaticimaging apparatus which incorporates the continuous use of a reusable,flexible imaging member in an imaging system in conjunction withfull-frame exposure.

10 Claims, 4 Drawing Figures PATENTEflum 10 m2 sum 1 or 4 INVENTORHAROLD E. CLARK ATTORNEY PATENTEmm 10 I972 SHEET 2 [IF 4 CONTINUOUSIMAGING APPARATUS BACKGROUND OF THE INVENTION This invention relates toa xerographic imaging system and more specifically to a novelxerographic imaging apparatus.

In the xerographic process as described in US. Pat. No. 2,297,691 anelectrostatic latent image is formed on a photoconductive insulatingplate and is developed through the deposition thereon of finely divided,electroscopic marking material referred to in the art as toner. Themarking material may be fixed to the surface of the photoconductiveplate or transferred to a sheet of copy paper to which it may bepermanently fixed. In most applications the photoconductive plate isinitially uniformly charged and then selectively exposed to a visiblelight image or other pattern of activating electromagnetic radiationwhereby the uniform charge is dissipated in the radiation struck areas,leaving a charge pattern which conforms to the electromagnetic radiationpattern applied. This exposure step is followed by development and theoptional transfer step.

It has been found that, as a general rule, a xerographic plate in theshape of a cylinder lends itself most readily to high speed processingby virtue of the fact that a xerographic plate of this nature may berotated successively past the various necessary xerographic processingstations in a substantially continuous manner utilizing the necessarydrive motors and clutch assembly arrangements. Thus, most commerciallysuccessful automatic or semiautomatic xerographic copying machinesinclude a cylindrical xerographic plate or drum with the xerographicprocessing stations located about the circumference of the drum in themachine. Therefore, in a majority of these machines a point on theperiphery of the cylindrically shaped xerographic plate in completingone processing cycle will rotate past a charging station, an exposurestation, a development station, a transfer station, and finally acleaning station. Although this type of machine configuration has beenproven to be very efficient because it provides for continuous movementof the xerographic plate through its processing cycle, the curvedperiphery of the plate imposes certain limitations upon plate exposure.Thus, cylindrical plates are usually exposed to an original to bereproduced by a scanning projection .technique in which only a verynarrow strip of the original, parallel to the longitudinal axis of thecylinder, is projected onto the moving cylindrically shaped xerographicplate at' any one time. In order to project the entire original onto thecylindrical xerographic drum the projector must scan the originalsynchronously with the rotation of the xerographic drum and the scanningspeed must be closely related to the peripheral speed of the drum so asnot to distort the image produced on the drum. Such an exposure systemgenerally requires fairly complex mechanisms which add to the expense ofthe apparatus as a whole. By utilizing a flat xerographic plate, thescanning exposure problems may be replaced by full-frame exposure of theoriginal. However, flat plates do not lend themselves to fast continuousxerographic processing the type which may be utilized with cylindricalplates. To the contrary, the handling problems associated with flatplates carried through automatic cycles are extremely complex anddifficult.

A configuration has previously been proposed which incorporatesfull-frame exposure in conjunction with cylindrical development andmultiple copying. Such an apparatus is described in U.S. Pat. No.3,190,199. However, the disclosed system requires that the xerographicplate be recycled by oscillating the plate in a direction opposite tothat of its normal rotational course thereby interrupting the continuousmotion of the process. While solving certain problems, therefore, theapparatus disclosed introduces other limitations which detract from theadvantages achieved.

SUMMARY OF THE INVENTION Therefore, it is an object of the presentinvention to provide an imaging system which will overcome the abovenoted disadvantages.

It is a further object of this invention to provide a novel xerographicimaging system.

It is a further object of this invention to provide a continuouselectrostatic imaging process capable of full-frame exposure.

Yet, still a further object of this invention is to provide a reusablexerographic imaging process utilizing a novel xerographic'apparatus.

Still another object of this invention is to provide a expedientxerographic system with built-in flexibility and high speed, highquality capabilities.

Yet, still another object of this invention is to provide a novelcontinuously rotating, high speed imaging system.

BRIEF DESCRIPTION The foregoing objects and others are accomplished inaccordance with the present invention generally speaking by providing asystem whereby an electrostatic latent image or charge pattern may beformed on the surface of a suitable support member such as aphotoconductive plate by a single full-frame exposure. The image supportmember is then wrapped around a rotatably mounted cylinder upon whichthe electrostatic charge pattern is developed and otherwise processedutilizing conventional techniques. The resulting developed image passesa transfer station which transfers the developer material in imagewiseconfiguration to a specific receiver sheet with the cylindercontinuously repeating the development and transfer cycle at continuoushigh speeds to produce a multiplicity of copies from the singleexposure. When copying is complete the image support member continuesforward to the exposure station at which it started for reimaging. Theconfiguration of the present invention hence provides a continuousmethod whereby multiple copies can be made from a single fullframeexposure on an image support member which is reusable once the desiredcopies have been obtained. The apparatus is designed so that therotating cylinder upon which the image support member is multiplydeveloped need never stop moving at high speed while at the same timethe image support member may be reexposed without varying its speed ordirection of movement of a non-moving original without the need ofmoving optical parts. In an alternate embodiment the apparatus of thepresent invention may be readily adapted to an induction imaging system,in which instance the need for cleaning the image support member iseliminated.

DETAILED DESCRIPTION The invention is further illustrated in theaccompanying drawings wherein:

FIG. 1 represents a side sectional view of the imaging apparatus of thepresent invention;

FIG. 2 represents a top view of the imaging apparatus of the presentinvention during the image exposure phase of the process;

FIG. 3 represents a top view of the imaging apparatus of the presentinvention during the copying stage of the process;

FIG. 4 represents a side sectional view of the imaging apparatus of thepresent invention used in conjunction with an induction imaging system.

Referring now to FIG. 1 there is seen an exemplary copying apparatus ofthe present invention generally designated 1 comprising rotatablymounted cylinders generally designated 2 and 3 the circumferences ofwhich are at least equal to the length of a standard size subject to becopied. An endless belt 4 revolves about the cylinders 2 and 3 in amanner such that the continuous belt contacts only the lateralextremities of the cylinders. This arrangement will become clearer infurther consideration of the subsequent illustrations described below.An image support member generally designated 6, represented in thepresent illustration as a flexible xerographic plate comprising aphotoconductive insulating layer overlying a conductive backing, ispresented as being attached or held laterally between the endless belt 4and the drive belt 42 and aspassing beneath the full frame exposurestation generally designated 10 comprising the original document to bereproduced 11, lens system 12 and light source 13.

Although for the purposes of the present illustration the electrostaticcharge pattern is-represented as being formed on a photoconductiveinsulating surface through the steps of charging the surface andselectively dissipating the charge by exposure to a pattern ofelectromagnetic radiation, other methods suitable for formingelectrostatic charge patterns may be used. For example, selectivedeposition of an electrostatic charge may be achieved by impressing acharge through an image stencil onto an insulating surface, imposing apotential on a shaped conductor or electrode, cathode ray tube imagepresentation of computer generated information to a uniformly chargedphotoconductive surface or the like. Thus, the image may be formedutilizing photosensitive materials, as herein illustrated, or by anysuitable technique such as one of the above mentioned conventionalmethods.

The image support member which bears the electrostatic charge patternmay consist of any suitable material capable of supporting anelectrostatic charge for sufficient time to permit multiple copying froma single, full frame exposure. Thus the image support member should havecharge retention properties. Typical materials found suitable arepolyethylene terephthalate, polytetrafluoroethylene, polyvinylfluoride,polyvinylchloride, styrene polymers, ethyl cellulose, cellulose acetate,polycarbonate resins, polyethylene and polypropylene.

When photoreceptors are utilized typical materials such as disclosed inUS. Pat. Nos. 3,121,006 and 3,121,007 have been found to besubstantially satisfactory. Other typical photoconductive materialsinclude selenium, sulfur, anthracene, inorganic photoconductive pigmentssuch as zinc oxide, lead oxide, cadmium sulfide, and cadmiumsulfoselenide, dispersed in binder resins, organic photoconductivepigments such as phthalocyanine, and sensitized polyvinylcarbazole, andhalogen doped selenium and arsenic-selenium alloy compositions asdisclosed in US. Pat. Nos. 2,803,542 and 3,312,548. Glass binder platessuch as disclosed in US. Pat. No. 3,151,982 are also representative ofthe type of plate which may be used in conjunction with the presentinvention. The conductive support materials utilized in conjunction withthe 'photoreceptors are those which present the desired flexibility sothat they may be used in conjunction with the process herein described.Typical conductive materials include aluminum, brass, copper, zinc,conductive paper, and any suitable plastic substrate having thenecessary conductivity properties.

Following exposure to the document to be reproduced 11 the image supportmember 6 is directed by the continuous belt mechanism 4 to the cylinder2 where the leading edge of the image support member is grasped byclamping means 15 or other equivalent fastening mechanism. The imagesupport member may be held to the continuous belt by any suitablemechanism such as clamps, a vacuum system, by engagingpins, a flatplate, or as herein illustrated, by a second continuously moving drivebelt, and when the image support member reaches the development cylinder2 .and is grasped by fastener 15, the means used to hold the imagesupport member to the continuous belt will automatically be disengagedas the clamp or fastening mechanism on the developer drum engages theleading edge of the support member. After having been engaged byfastener 15 the image support member passes'a developing unit generallydesignated 20 of the cascade type as more fully described in US. Pat.Nos. 2,618,551, 2,618,552 and 2,638,416. Although any of theconventional xerographic development techniques may be utilized theillustrated cascade unit described below has been found to be one of themore effective development systems. The development unit 20 includes anouter container 21 with a trough at its bottom containing a supply ofdeveloper material 22. This developer material is picked up from thebottom of container 21 and dumped or cascaded over the surface of theimage support member by a number of buckets 23 on an endless drivenconveyor belt 24. This development technique utilizes a two componentdevelopment mixture including finely divided, electroscopic markingparticles or toner and larger carrier beads. The carrier beads serveboth to deagglomerate the toner particles and to charge them by virtueof their relative position with respect to the toner in thetriboelectric series. Fn'ction between the beads and toner particlesduring tumbling of the developing mixture causes particlesto charge toopposite polarities so that the toner particles cling to the carrierbeads. When the carrier beads with the toner particles clinging theretoare cascaded over the image support member the electrostatic fields fromthe latent electrostatic charge pattern on the member pulls the tonerparticles off the carrier beads thus serving to develop the image. Thecarrier beads, along with any toner particles not used to develop theimage, fall back into the trough at the bottom of container 21 for reusewith the toner being periodically replenished.

Following the development step the image support member or plate isrotated so that the electrostatic latent image contacts sheets of copypaper presented one at a time by way of rollers 30 which bring eachsheet into contact with the plate surface as it rotates around oncylinder 2. The developer particles are transferred in imagewiseconfiguration to the cut sheets of paper by any suitable technique suchas by applying a charge to the back of the sheets with a coronagenerating unit 33. The corona discharge unit 33 is connected to asource of high potential in the transfer stepso that it deposits acharge on the back of the copy paper which is opposite in polarity tothe charge of the toner particles used to develop the latent image. Thischarge on the back of the paper pulls the toner particles away from theplate by overcoming the force of attraction between the particles andthe charge on the plate. The transfer potential is regulated in such amanner so as not to destroy the latent image on the image support membersuch as disclosed, for example, in US. Pat. No. 2,951,443. It should benoted at this point that any suitable transfer technique may be utilizedsuch that the requirements of the present invention are satisfied. Forexample, a roller connected to a high potential source opposite inpolarity to thetoner particles may be placed immediately behindand incontact with the paper to attract the particles, or the copy paper or acopy web used in place of the paper may have an adhesive surface whichwill attract the toner particles. The sheets then pass between the plate6 and the conductive belt 35 which is connected to ground'through aconductive roller 36. It has been found that this type of ground orconductive contact serves to separate the copy sheet with itstransferred image from the plate without effecting the electrostaticlatent image. The separated copy sheet is then picked up by rollers 36and fed past a resistance heating unit 37 which serves to permanentlyaffix the toner image to the cut copy paper. Other techniques may beutilized to fix the transfer toner image to its subsequent support suchas the utilization of solvent vapor fixing, by spraying the toner imagewith an overcoating or by laminating. The finished copies are then fedto a delivery tray 39 by way of rollers 38.

The development cylinder 2 bearing the image support member thencontinues to rotate according to a preestablished signal designating thenumber of copies to be reproduced from the initial exposure. Followingcompletion of the reproduction of the desired number of prints the imagesupport member is reengaged by the continuous belt in response to apredetermined signal while simultaneously being disengaged from thedevelopment cylinder without a change in speed. The image support memberis guided onto the surface of belt 4 by the lip of the drive belt 42.The image support member now being driven by the continuous belt 4 movespass cleaning brush 40 around cylinder 3 and beneath corona generatingunit 41 which serves to recharge or sensitize the plate. Although othercharging devices known to those skilled in the art of xerography may beutilized it is preferred to charge the photoconductive insulatingsurface of the present illustration by corona discharge from a wirefilament or filament array which is maintained at a high potential suchas described in US. Pat. Nos. 2,588,699, 2,836,726, or 2,778,946. Coronacharging unit 33 is thus similar to unit 41. Following sensitization theimage support member then reenters the exposure area and is ready to bereimaged by full-frame exposure to a second document.

Since the continuous endless belt mechanism 4 operates synchronouslywith the rotating cylinders 2 and 3 and the drive belt 42, the speeds ofthe endless belt, the drive belt and the development cylinder 2 are thesame, and all three systems continue to rotate at high speeds until thedesired number of exposures and copies are made. Inasmuch as the imagesupport member following exposure is transferred by disengagement to thedevelopment cylinder both rotatingcylinders 2 and 3 may be utilized todrive the continuous belt mechanism. However, if desirable, the beltmechanism may be situated outside the lateral extremities of thecylinders. Guide bars 43 function to maintain the image support memberin a planar condition during exposure and add further support to thebelts where located.

FIG. 2 represents a plane view of the imaging apparatus of the presentinvention during the exposure phase. Referring now to FIG. 2 there isseen the endless belt mechanism 4 which is driven by the rotatablymounted cylinders 2 and 3. The image support member 6 in the exposureposition rests between the drive belt 42 which is juxtapositioned withrespect to the endless belt 4 such that the plate is held taut by theguide bar 43 so that no distortion in the image is realized. If desiredother suitable techniques may be used so as to contribute to maintainingthe image support member in a planar condition during exposure. However,under normal operating conditions, generally used image support membersare adequately maintained in the planar condition as a result of normalpressure applied by the drive belt and bar to the endless belt surface.Fasteners 15 are located on the development cylinder 2 which serve tograsp the leading edge of the image support member following exposure.The developer unit 20 is seen in close proximity to the developercylinder 2 and the brush cleaner 40 and corona unit 41 are similarlylocated in relationship to cylinder 3.

FIG. 3 represents the apparatus illustrated in FIGS. 1 and 2 wherein theimage support member is now in its development position. The imagesupport member 6 has left the drive belt 42 and has been engaged byfasteners 15. The image support member is then presented to thedeveloper station 20 to complete the copying phase of the process. Whenthe desired number of copies have been made, the fasteners release theimage support member and it is guided by the leading lip of drive belt42 (best illustrated in FIG. 1) onto the surface of the endless belt 4and is returned by way of roller 3 to the exposure station. Cleaningbrush 40 and corona unit 41 are again represented as in FIGS. 1 and 2.

Reference is now made to FIG. 4 wherein there is illustrated anembodiment whereby the apparatus of the present invention is used inconjunction with induction imaging and development. Anelectrophotographic plate, generally designated 50, comprising aphotoconductive insulating layer overlying a conductive backing memberis disclosed. Plate 50 moves first through charging station 61, nextthrough the flash exposure station 71 and is then engaged by means anddirected to image induction station generally designated 81. Whenimaging is complete the image support member 50 is directed to erasestation 91 following which the image support member or xerographic platemay be recycled in a continuous manner. The charging station 61 issimilar to the corona discharge units discussed in FIG. 1. When theimage support member reaches the induction station 81 an insulatingrectifying layer 82 supplied from supply spool 83 is contacted with theimaged surface of the image support member by way of roller 84 which, asillustrated in the embodiment, is maintained at ground potential. Speedof movement of rectifying insulator 82 is synchronized with the speed ofrotation of the image support member 50 wrapped around roller 49. Chargepatterns are induced on the surface of rectifying insulator 82 asdescribed more fully in U.S. Pat. No. 3,172,024. The rectifyinginsulating layer 82 may in this embodiment comprise a layer of zincoxide in an insulating binder overlying a conductive backing such asmetal foil or paper in a conductive condition or the like. A morecomplete discussion of the materials utilized and conditions applied tothe induction imaging system herein referred to may be found in theabove cited patent and said patent is herein incorporated by reference.Following image induction the image rectifying insulator 82 is movedthrough processing station 86 where the image is developed and fixed.Development techniques such as the above described cascade developmentprocess may be utilized. Following processing the insulator 82 isrewound on spool 85. As is well known in the art these webs may be cutinto proper lengths and stacked rather than fed to take up spools asshown. In this embodiment there is illustrated one charge inductionstation. However, it should be realized that in employing the conceptsherein described the original image is in no way affected ordeteriorated while charge is induced into an adjacent member.Accordingly, although only one station is shown any number of stationsmay be positioned around a charge inducing member, or a charge inducingmember may be moved into contact with an insulating rectifier to inducecharge into such rectifier substantially any number of times. Followingthe copying of the desired number of prints the image support member 50is directed back onto the surface of and to be driven by the continuousendless belt 48 and carried to the erase station 91 over roller 51where, in the case of a photoconductive insulating layer, it may beuniformly illuminated with light to erase the charge pattern from itssurface and thus prepare the plate for recycling. Alternatively,however, eraser may be omitted and the plate may be recycled immediatelyto charging station 61 to reestablish a charge at a level to yield auniformly charged plate. Plate 50 is then directed towards exposurestation 71 by the belts 46 and 48 and is ready for re-exposure andfurther utilization without interruption. Guide bars 47 are againutilized to maintain the image support member rigid during imaging andsecondarily to add support where located.

Although the present invention has been generally illustrated inconjunction with cascade development any suitable development means maybe used. Typical development techniques include powder cloud developmentas more fullydescribed in U.S. Pat. Nos. 2,725,305 and 2,918,910,magnetic brush development more fully described in U.S. Pat. Nos.2,791,949 and 3,015,305 andthe above described cascade system.

Although the present invention has been described with respect to aspecific structural arrangement and configuration it is to be understoodthat it is not intended that the apparatus of the present invention benecessarily restricted to the design as set out herein and it isintended to include all similar configurations which will satisfy therequirements of the present invention. For example, numerous techniquesmight be employed for engaging and disengaging the image support memberas it passes to the surface of the development cylinder and thestructure of the belts may take on various configurations. In addition,if the speeds are so high that blurring of the image might occur, thelens could be given a small lateral motion in order to compensate formotion. Furthermore, although one of the advantages of the presentinvention is to present a system which is readily adapted to full frameflash exposure this is not to say that other forms of exposure cannot beused if desired such as optical scanning as disclosed in U.S. Pat. Nos.3,062,094, 3,l00,l l2 and 3,221,622.

Anyone skilled in the art will have other modifications occur to himbased on the teachings of the present invention. These modifications areintended to be encompassed within the scope of this invention.

What is claimed is:

1. A copying apparatus comprising in combination:

a. an image support member;

b. a rotatably mounted cylinder for driving said imaging support member;

c. a pressure means for holding said image support member in a planarcondition, said pressure means comprising an endless belt configurationwhich contacts only the lateral extremities of said image support memberand is juxtapositioned to said drive means;

. meansfor forming an electrostatic latent image by full frame exposureon the surface of said image I support member while said member is heldin said planar condition;

e. means for wrapping said image support member about said rotatablymounted cylinder;

f. means for processing said electrostatic charge pattern on said imagesupport member to produce at least more than one image reproduction; and

g. means to return said image support member in a continuous manner tosaid exposure means so as to prepare said member for another cycle forfull frame exposure and rapid processing.

2. The apparatus as disclosed in claim 1 wherein said processing meanscomprises a means for developing said electrostatic latent image withelectroscopic developer material and means for transferring saiddeveloper material from said support member in imagewise configurationto the surface of a receiving substrate, said developing and transfermeans being positioned adjacent to said rotatably mounted cylinder.

3. The apparatus as disclosed in claim 2 further including cleaningmeans for removing residual developer material from said image supportmember.

4. The apparatus as defined in claim 1 wherein said image support membercomprises a flexible, reusable xerographic plate comprising aphotoconductive insulating layer superimposed upon a conductivesubstrate.

5. The apparatus as disclosed in claim 4 wherein said processing meanscomprises a means for developing said electrostatic latent image withelectroscopic developer material and means for transferring saiddeveloper material from said support member in imagewise configurationto the surface of a receiving substrate, said developing and transfermeans being positioned adjacent to said rotatably mounted cylinder.

6. The apparatus as defined in claim 5 further including a means forremoving residual developer material from said xerographic plate andmeans for uniformly recharging said xerographic plate.

7. The apparatus as disclosed in claim 1 wherein said processing meanscomprises at least one induction imaging and developer means positionedadjacent to said rotatably mounted cylinder, said developer meansadapted to deposit electroscopic marking particles on said electrostaticlatent image.

8. The apparatus as disclosed in claim 7 further including a means forerasing residual charge from said image support member.

9. A copying apparatus comprising in combination an image supportmember, a rotatably mounted cylinder for driving said image supportmember, a pressure means adapted to hold said image support member in aplanar condition during exposure said pressure means comprising anendless belt configuration which contacts only the lateral extremitiesof said imaging support member and is juxtapositioned to said drivemeans, means for forming an electrostatic latent image by full frameexposure on the surface of said image support member while said memberis held in said planar condition, means for wrapping said image supportmember about said rotatably mounted cylinder, means for developing saidelectrostatic latent image with electroscopic marking materials, meansfor transferring said developer from said image support member inimagewise configuration to the surface of a receiving substrate, saiddeveloping and transferring means being positioned adjacent to saidrotatably mounted cylinder, said cylinder being adapted to recycle saidimage support member past said developing and transferring means so asto produce at least more than one image of the original, means forreturning said image support member in a continuous manner to saidexposure means so as to prepare said member for reexposure and means forcleaning residual developer material from said image support member.

10. The apparatus as disclosed in claim 9 wherein said image supportmember comprises a flexible, reusable, electrophotographic platecomprising a photoconductive insulating layer superimposed upon aconductive substrate.

it: t =0:

1. A copying apparatus comprising in combination: a. an image supportmember; b. a rotatably mounted cylinder for driving said imaging supportmember; c. a pressure means for holding said image support member in aplanar condition, said pressure means comprising an endless beltconfiguration which contacts only the lateral extremities of said imagesupport member and is juxtapositioned to said drive means; d. means forforming an electrostatic latent image by full frame exposure on thesurface of said image support member while said member is held in saidplanar condition; e. means for wrapping said image support member aboutsaid rotatably mounted cylinder; f. means for processing saidelectrostatic charge pattern on said image support member to produce atleast more than one image reproduction; and g. means to return saidimage support member in a continuous manner to said exposure means so asto prepare said member for another cycle for full frame exposure andrapid processing.
 2. The apparatus as disclosed in claim 1 wherein saidprocessing means comprises a means for developing said electrostaticlatent image with electroscopic developer material and means fortransferring said developer material from said support member inimagewise configuration to the surface of a receiving substrate, saiddeveloping and transfer means being positioned adjacent to saidrotatably mounted cylinder.
 3. The apparatus as disclosed in claim 2further including cleaning means for removing residual developermaterial from said image support member.
 4. The apparatus as defined inclaim 1 wherein said image support member comprises a flexible, reusablexerographic plate comprising a photoconductive insulating layersuperimposed upon a conductive substrate.
 5. The apparatus as disclosedin claim 4 wherein said processing means comprises a means fordeveloping said electrostatic latent image with electroscopic developermaterial and means for transferring said developer material from saidsupport member in imagewise configuration to the surface of a receivingsubstrate, said developing and transfer means being positioned adjacentto said rotatably mounted cylinder.
 6. The apparatus as defined in claim5 further including a means for removing residual developer materialfrom said xerographic plate and means for uniformly recharging saidxerographic plate.
 7. The apparatus as disclosed in claim 1 wherein saidprocessing means comprises at least one induction imaging and developermeans positioned adjacent to said rotatably mounted cylinder, saiddeveloper means adapted to deposit electroscopic marking particles onsaid electrostatic latent image.
 8. The apparatus as disclosed in claim7 further including a means for erasing residual charge from said imagesupport member.
 9. A copying apparatus comprising in combination animage support member, a rotatably mounted cylinder for driving saidimage support member, a pressure means adapted to hold said imagesupport member in a planar condition during exposure said pressure meanscomprising an endless belt configuration which contacts only the lateralextremities of said imaging support member and is juxtapositioned tosaid drive means, means for forming an electrostatic latent image byfull frame exposure on the surface of said image support member whilesaid member is held in said planar condition, means for wrapping saidimage support member about said rotatably mounted cylinder, means fordeveloping said electrostatic latent image with electroscopic markingmaterials, means for transferring said developer from said image supportmember in imagewise configuration to the surface of a receivingsubstrate, said developing and transferring means being positionedadjacent to said rotatably mounted cylinder, said cylinder being adaptedto recycle said image support member past said developing andtransferring means so as to produce at least more than one image of theoriginal, means for returning said image support member in a continuousmanner to said exposure means so as to prepare said member forreexposure and means for cleaning residual developer material from saidimage support member.
 10. The apparatus as disclosed in claim 9 whereinsaid image support member comprises a flexible, reusable,electrophotographic plate comprising a photoconductive insulating layersuperimposed upon a conductive substrate.